Qian-Kun-Nin, a Chinese herbal medicine formulation, attenuates mitochondrial oxidant stress in cardiomyocytes

Qian-Kun-Nin is a Chinese herbal medicine formulation used for several indi cations, including the treatment of cardiovascular diseases. This formulati on contains herbs which possess antioxidant properties. In this study, Qian -Kun-Nin's ability to confer protection to cardiomyocytes against reactive oxygen species (ROS) generated during mitochondrial electron transport inhi bition was tested. The intracellular fluorescent probe 2',7'-dichlorofluore scin diacetate (DCFH-DA, sensitive to H2O2 and hydroxyl radicals) was used to assess intracellular ROS, and propidium iodide (PI) was used to assess v iability in cultured chick embryonic cardiomyocytes. Qian-Kun-Nin significa ntly attenuated oxidation of DCFH in cells exposed to the mitochondrial sit e III inhibitor, antimycin A, consistent with a decrease in oxidative stres s. These attenuated oxidant levels were associated with improved cell survi val. After antimycin A exposure, Qian-Kun-Nin decreased cell death from 51. 6 +/- 3.3% in untreated cells to 27.3 +/- 3.8% in treated cells at 2 h. We conclude that Qian-Kun-Nin attenuates oxidant stress and protects cells fro m lethal oxidant damage during mitochondrial electron transport inhibition, and thus its therapeutic potential in treating cardiovascular diseases may relate to its antioxidant properties. (C) 2001 Elsevier Science Ireland Lt d. All rights reserved.